[GraemeJ]

The fact is, this update was inadequately tested and should not have been released.  It makes me wonder if MobileSheets Pro is ready for prime time.  A glitch like this would be disastrous for anybody using it in a performance. 

I don't think you will get much support from the users of this software for your point of view.  

Mike's support goes way beyond what we have come to expect from much bigger companies.  Occasionally, something slips past the development stage - even the great God Microsoft has released 'updates' that made things worse (and took longer to fix than this one).  Geoff's advice is exactly what we should all take, never update anything you are going to immediately rely on functioning correctly and always do a backup first.